A configuration file that is web.config is mainly used for managing various settings that defined a website. These all settings are stored in XML files that are separate from our application code. In this way we can configure settings independently from our code easily. Usually a website contains only a single Web.config file stored inside an application root directory. However there may be many configuration files that manage settings at various levels within the application.

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The web.config files are the files which are stored in XML format files which makes them easy to use and access. An infinite number of directories and sub-directories is created for each Web.config files and similarly you can create an infinite number of “web.config” files for any number of application. All web.config files inherit their respective parent directories. For example, if anyone has to make changes to the web.config file, then the change can be implemented instantaneously without rebooting the system.